HIV is sexually untransmittable when viral load is undetectable

In 2008, the Swiss National AIDS Commission (Commission fédérale pour les problèmes liés au sida) controversially made the claim that people infected with HIV who are adhering to an effective antiretroviral therapy (ART) do not transmit HIV. 1 Vernazza P Hirschel B Bernasconi E et al. Les personnes séropositives ne souffrant d'aucune autre MST et suivant un traitement antirétroviral efficace ne transmettent pas le VIH par voie sexuelle. Bulletin des médecins suisses. 2008; 89: 165-169 Crossref Google Scholar Subsequently, a modelling study in 2009 gave rise to the concept of treatment as prevention and then the UNAIDS 90-90-90 campaign that suggested that if countries could attain 90% HIV testing in their population, ensure that 90% of those individuals were on ART, and 90% of those were fully suppressed, then sexual HIV transmission would drop to low levels. 2 Granich RM Gilks CF Dye C De Cock KM Williams BG Universal voluntary HIV testing with immediate antiretroviral therapy as a strategy for elimination of HIV transmission: a mathematical model. Lancet. 2009; 373: 48-57 Summary Full Text Full Text PDF PubMed Scopus (1557) Google Scholar , 3 UNAIDS90-90-90—an ambitious treatment target to help end the AIDS epidemic. https://www.unaids.org/sites/default/files/media_asset/90-90-90_en.pdfDate: 2014 Date accessed: June 10, 2023 Google Scholar But it was only after the results of the HPTN 052 study in 2016 that the secondary HIV prevention benefits of ART were fully seen. 4 Cohen MS Chen YQ McCauley M et al. Antiretroviral therapy for the prevention of HIV-1 transmission. N Engl J Med. 2016; 375: 830-839 Crossref PubMed Scopus (1134) Google Scholar The HPTN 052 global trial in which 1763 sero-discordant couples were randomly assigned to either an early ART group or deferred ART group, substantiated that no linked HIV transmission occurred between discordant couples in which the partner living with HIV was virally suppressed on ART. Laura N Broyles and colleagues' systematic review in The Lancet further supports the almost zero risk for sexual transmission of HIV at levels less than 1000 copies per mL. 5 Broyles LN Luo R Boeras D Vojnov L The risk of sexual transmission of HIV in individuals with low-level HIV viraemia: a systematic review. Lancet. 2023; (published online July 23.)https://doi.org/10.1016/S0140-6736(23)00877-2 Summary Full Text Full Text PDF PubMed Scopus (12) Google Scholar The authors examined this concept and other evidence for sexual HIV transmission risk linked to viral load in published studies and abstracts from 2010 to 2020, and other identified recommended studies before 2010 and found sexual HIV transmission to be absent in cases involving less than 600 copies per mL and exceedingly rare in cases of less than 1000 copies per mL. The risk of sexual transmission of HIV in individuals with low-level HIV viraemia: a systematic reviewThere is almost zero risk of sexual transmission of HIV with viral loads of less than 1000 copies per mL. These data provide a powerful opportunity to destigmatise HIV and promote adherence to ART through dissemination of this positive public health message. These findings can also promote access to viral load testing in resource-limited settings for all people living with HIV by facilitating uptake of alternative sample types and technologies. Full-Text PDF Open Access